General
– Imagine a 16 Bit File with Full Resolution Samples that actually Misses the Peaks in the Audio, so when the Audio is Re-Constructed the Peaks then Added Could at least be 3dB Higher than the Sample we had Not Take
– so if we Work Closer to a Digital Headroom (e.g. Towards -1 or -2 dB FS), it is possible that the Re-Constructed Audio will go Beyond the Headroom and we get Distortion
- a Conventional Limiter Reads only Actual Samples, whereas a TP Limiter reads whats Going on in-between the Samples
– in your DAW, All the Metering is Based on a Sample Peak Programme Meter
- when you Bounce the File within you DAW you Create a Digital File, but this has to Be Converted Back to Analogue Before you can Hear it
– as a Part of this Conversion a Re-Construction Filter is Applied to Round Off the “Stepped Digital Audio Signal”, which Gives us a Smooth Listening Experience
– but these Filters can Cause Slight Changes in the Levels of the Audio
– i.e. for Signals that are Close to 0dBFS this can be a Problem as Rounded Peaks can Cause Clipping
– a High End (HiFi Speaker System) Digital to Analog Converter has Headroom to Compensate for this Issue, but Cheap Speakers Not
– so Inter Sample Peaks Mean that Audio with a Peak of 0dBFS might Distort in the Analogue Realm
– to Solve this Issue there are True Peak Meters which Indicate the Clipping and True Peak Limiters to Prevent Clipping
True Peak Problems with Lossy Codecs
– Lossy Codecs are Required for Streaming Services to Save Bandwidth
– but Lossy Codecs Do Not Handle High Volume as Good as Lossless Formats, you Do Need to Monitor and Control Very Close to Digital Headroom
– Digital Audio is the same as Film, it is Made of a Series of Samples or Digital Snapshots
– a Traditional Peak Meter (usually at 44.100 Times per Second), Does Not Show what is Going On between the Samples or Snapshots
– so when you Convert Back to Analog, what is between the Samples or Snapshots can Lead to a Boost of 6dB Above Digital Headroom = Intersample Peaks or True Peak (TP)
– so you Need Tools and Limiters that Work to the True Peak Information, because they Show what is Likely to Happen between the Samples when you Convert Audio Back into Analog
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